14．口算
0 162547 162555 162561 162565 162571 162573 162577 162583 162585 162591 162597 162601 162603 162607 162613 162615 162621 162625 162627 162631 162633 162637 162639 162641 162642 162643 162645 162646 162647 162649 162651 162655 162657 162661 162663 162667 162673 162675 162681 162685 162687 162691 162697 162703 162705 162711 162715 162717 162723 162727 162733 162741 199269
| $\frac{4}{5}$+$\frac{1}{5}$= | 597×4≈ | 49×9≈ | 200×5= |
| 50+480= | 1-$\frac{3}{8}$= | 123×2= | 49+35= |
| 21×5= | 56÷8= | $\frac{7}{9}$-$\frac{4}{9}$= | 315×0= |